Peter Ladefoged, a leading linguist phonetician who traveled the world to document the distinct sounds of endangered languages and pioneered ways to collect and study data, has died. He was 80.

Ladefoged, a University of California, Los Angeles professor emeritus, died Tuesday at a London hospital after becoming ill following a research trip to India, the university announced.

When Ladefoged entered the field in the late 1950s, he married linguistic field work and phonetics in a new way, a UCLA linguistics professor, Pat Keating, said.

“He did extensive linguistic field work on a scale it had not been done before, and when he brought it back from the field, he found ways to use sophisticated laboratory equipment to analyze his recordings,” she said.

Ladefoged – pronounced by saying all of the vowels – also pioneered the use of state-of-the-art equipment in the field. His first portable phonetics lab that included a tape recorder and various scientific instruments required a porter and weighed 100 pounds but enabled him to do more than listen – he could take quantitative measurements such as gauging how much air escapes from the nose or throat when a sound is made.

In an earlier trip to India, he recorded the Toda language, which is spoken by fewer than 1,000 people, as he documented its six different trills produced by the tip of the tongue. In the Kalahari Desert, he studied the click sound native to Africa. In America, an Indian tribe that knew their language was vanishing refused to cooperate because they didn’t want to reveal their culture to outsiders.

Soon after moving to Los Angeles from Scotland to become an assistant professor at UCLA in 1962, Ladefoged had a brief career in Hollywood as the chief linguist consultant on the 1964 film “My Fair Lady.”

Director George Cukor wanted him to teach the film’s star, Rex Harrison – who would end up winning an Oscar for the role of Professor Henry Higgins – to behave like a phonetician.

“My immediate answer was, ‘I don’t have a singing butler and three maids who sing, but I will tell you what I can as an assistant professor,'” Ladefoged told the Los Angeles Times in 2004.

Ladefoged helped set up the film set’s phonetics laboratory, taught Harrison to read phonetic symbols – and ate the cookies that the film’s co-star, Audrey Hepburn, baked for crew members.

“I’d never heard of Cukor. It just struck me as the chance to earn a fortune each week,” Ladefoged said. “It was just so much more than a professor’s salary. It paid me enough to buy my first car in America.”

The professor’s voice is preserved on the soundtrack. When Professor Higgins stomps down the stairs, he knocks a record player that starts playing a recording of Ladefoged making vowel sounds.

Peter Nielsen Ladefoged was born September 17, 1925, in Sutton, England, to Niels, an importer of Danish bacon and cheese, and his wife, Marie Frances.

After serving in the British army near the end of World War II, Lade foged enrolled in the University of Edinburgh in Scotland. He intended to study English literature but soon became fascinated by the sounds of speech.

“I wanted to find out why Shelley could write better-sounding poetry than I,” he told the Times in 1970.

Ladefoged never answered that question but earned a master’s and then a doctorate in phonetics in 1959 at Edinburgh. He returned to Nigeria, where he had already spent a year, to record speakers of about 60 different languages.

Within a few years, he had traveled to Africa, Mexico, India, and Uganda. Later, he went to Australia, Papua New Guinea, China, Brazil, and many other countries.

When he got married in 1953, his wife, Jenny, she became his collaborator. He promised they would visit every continent, and they did.

The 6-foot-tall, genial professor was known for his sense of humor. In his email address, Ladefoged called himself “old fogey.”

One of the 10 books he published, “A Course in Phonetics,” was just released in its fifth edition and is used widely in college classrooms. “Sounds of the World’s Languages” (1996), written with his research partner Ian Maddieson, described every sound the pair had come across and became a prominent reference work.

Although Ladefoged predicted that all but a handful of the world’s 6,500 languages would disappear over the next 1,000 years, he said that linguists should record languages but not necessarily try to save them.

Preserving languages, he argued, could weaken national unity, encourage tribalism, and absorb scarce resources that might otherwise be used for development.

Deciding what language people should speak is “not our decision to make,” Ladefoged told National Public Radio in 1999. “It’s up to the people themselves.”